BIOREACTOR ASSEMBLY, BIOREACTOR, AND METHOD OF OPERATING SAME
A bioreactor capable of producing complex, three-dimensional tissue constructs has improved media transfer and increased controllability with regard to exposure to the external environment. The bioreactor includes an external surface, a first tissue culture side for culturing a first cell source in a first tissue culture support region, a second tissue culture side for culturing a second cell source in a second tissue culture support region, and a plurality of ports. At least one of the ports of the plurality of ports extend from the first tissue culture support region of the first tissue culture side to the external surface. The plurality of ports can include an external port that is configured to be a liquid inlet when the bioreactor is in a first orientation and a gas outlet when the bioreactor is in a second orientation.
This invention was made with government support under grant contract number 1448937 awarded by the National Science Foundation (NSF). The government has certain rights in the invention.
FIELDThis invention relates generally to bioreactors, and more particularly to bioreactors that facilitate the formation of complex three-dimensional and multi-phasic tissue constructs.
BACKGROUNDA bioreactor, such as the bioreactor described in U.S. application Ser. No. 15/211,501 filed. Jul. 15, 2016 (now U.S. Pat. No. 10,167,444), which is incorporated by reference herein in its entirety, can allow for the production of complex three-dimensional tissue constructs. With such bioreactors, improved media transfer is desirable, as it can help facilitate improved growth of the three-dimensional tissue construct. Further, more precise control of exposure to the external environment can help with various aspects including portability, such as when the tissue construct is transported to the operating room in advance of a surgical procedure.
SUMMARYAccording to one embodiment, there is a bioreactor, comprising: an external surface; a first tissue culture side for culturing a first cell source in a first tissue culture support region; a second tissue culture side for culturing a second cell source in a second tissue culture support region; and a plurality of ports. At least one of the ports of the plurality of ports extends from the first tissue culture support region of the first tissue culture side to the external surface.
According to various implementations, the bioreactor may further include the following features or any technically-feasible combination of some or all of these features:
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- the plurality of ports includes an external port that is configured to be a liquid inlet when the bioreactor is in a first orientation and a gas outlet when the bioreactor is in a second orientation;
- the external port opens from the external surface into a perimeter channel;
- the first tissue culture side and the second tissue culture side are made from a transparent plastic material;
- the first tissue culture support region includes a first tissue culture support surface and the second tissue culture support region includes a second tissue culture support surface;
- the first tissue culture support surface supports two or more separate tissue culture plates and the second tissue culture support surface supports a single tissue culture plate;
- two media collection reservoirs are situated below the two or more separate tissue culture plates;
- the two media collection reservoirs include corner projections to help stabilize or position the two or more separate tissue culture plates;
- the two or more separate tissue culture plates are joined to the single tissue culture plate with a plurality of interiorly extending tissue guides;
- the interiorly extending tissue guides are angled such that a distance between the interiorly extending tissue guides is greater at the two or more separate tissue culture plates than a distance between the interiorly extending tissue guides at the single tissue culture plate;
- the first tissue culture support surface is a doubly recessed area that includes a port side wall having port openings from the plurality of ports;
- the port side wall recesses the first tissue culture support surface away from a sloped media support surface;
- the sloped media support surface has four angled walls that converge toward the first tissue culture support surface;
- an angle of each angled wall of the four angled walls is between 3° and 10°, inclusive;
- the plurality of ports includes feeding ports and seeding ports, and the seeding ports are located closer to the sloped media support surface than the feeding ports;
- the plurality of ports includes an internal port that extends partly into the first tissue culture side or the second tissue culture side to house a non-invasive sensor; and/or
- the first tissue culture side includes a lid recess to accommodate an extending ridge on the second tissue culture side.
According to another embodiment, there is provided a bioreactor, comprising: an external surface; a tissue culture side; and an external port extending between the tissue culture side and the external surface. The external port is configured to be a liquid inlet when the bioreactor is in a first orientation and a gas outlet when the bioreactor is in a second orientation.
According to another embodiment, there is provided a bioreactor, comprising: a tissue culture support region having a media collection reservoir, wherein the media collection reservoir is configured to accommodate at least a portion of an interiorly extending tissue guide.
According to another embodiment, there is provided a bioreactor comprising a first tissue culture side for culturing a first cell source; a second tissue culture side for culturing a second cell source; and a sloped media support surface. The sloped media support surface converges toward a tissue culture support surface in the first tissue culture side or the second tissue culture side.
It is contemplated that any number of the individual features of the above-described embodiments and of any other embodiments depicted in the drawings or description below can be combined in any combination to define an invention, except where features are incompatible.
Example embodiments will hereinafter be described in conjunction with the appended drawings, wherein like designations denote like elements, and wherein:
A bioreactor capable of producing complex three-dimensional tissue constructs, such as the bioreactor described herein, can promote the accessibility and availability of a diverse array of tissue constructs for various treatment and research purposes. Given that the bioreactor is structured to produce complex three-dimensional tissue constructs, there can be unique challenges when it comes to issues such as media transfer. The bioreactor disclosed herein facilitates improved media transfer through the use of various ports and other features detailed further below. Improved media transfer can promote tissue formation. Further, the bioreactor assembly has increased controllability with regard to exposure to the external environment.
Complex three-dimensional tissue constructs can include multiple tissue constructs formed from multiple cell sources, and more particularly, complex three-dimensional tissue constructs can include multi-phasic tissue constructs that include multiple tissue constructs cultured from cell sources with one or more of the cell sources containing different cell types e.g., bone and ligament cells). The bioreactor can allow for cells of two or more different sources to be grown independently and then co-cultured to fabricate a scaffold-free, multi-phasic three-dimensional engineered tissue with two or more different types of tissue in the final product. The bioreactor can be a stand-alone culture device or part of an assembly that comprises numerous bioreactors and a perfusion system, as detailed further herein, for example. The bioreactor can allow for the formation of continuous, multi-phasic tissue constructs without any internal manipulation by the technician, thereby minimizing contamination risk. In addition to minimizing contamination risk, a closed bioreactor system can precisely control and maintain the tissue culture environment. Tissue growth and development is highly responsive to environmental factors (pH, temperature, nutrient concentration, etc.), and as such, the entire fabrication process can impact the integrity of the final product. The bioreactor disclosed herein can facilitate such an improved fabrication process, and advantageously, the complex three-dimensional tissue construct can remain in a closed or partially closed environment until it is ultimately needed for patient or researcher use. Through the elimination of manual, user-dependent processes, the bioreactor and method facilitate an automated system and process that can eliminate user variability and that promotes tissue construct consistency. Tissue manufacturing times may be reduced, and production capacity may be increased. Further, the system may be modular, capable of incorporating multiple bioreactors into a larger centrally controlled assembly while, in some embodiments, maintaining a relatively small overall volume to minimize the space required to manufacture the tissue constructs.
The first tissue culture side 42 acts as a base for culturing a first cell source (e.g., bone cells), while the second tissue culture side 44 acts as a lid. When the bioreactor 12 is inverted, the second tissue culture side 44 acts as a base for culturing a second cell source (e.g., ligament cells), while the first tissue culture side 42 acts as a lid. In an advantageous embodiment, the bioreactor 12 is used for the fabrication of scaffold-free bone-ligament-bone (BLB) multi-phasic tissue constructs. However, other cell types can be used, particularly those that form a spontaneously delaminating tissue monolayer or those that are capable of substrate controlled tissue monolayer delamination (e.g., muscle tissue, nerve tissue, etc.). Many cell culture bioreactors are designed for non-adherent cell suspension or cell expansion, but it should be understood that these devices do not provide the means of capturing and co-culturing delaminated monolayers of multiple tissue types required for the formation of multi-phasic tissue constructs, such as BLB tissue constructs. Further, it is possible to have more tissue culture sides than what is illustrated herein, which can be used to fabricate other multi-phasic tissue constructs.
The first tissue culture side 42 and the second tissue culture side 44 generally define an interior area 46 where the tissue construct is formed. The interior area 46 is generally shielded from the external environment, with the exception of external ports 48, 50, 52 which may be a part of a port assembly 54, which is detailed further below. External surfaces 56, 58 of the respective sides 42, 44 are exposed to the external environment on the outside of the bioreactor 12. Regulating the environment within the interior area 46 can help promote multi-phasic tissue construct formation at a first tissue culture support region 60 associated with the first tissue culture side 42 and at a second tissue culture support region 62 associated with the second tissue culture side 44.
The first tissue culture support region 60 includes a first tissue culture support surface 64, and the second tissue culture support region 62 includes a second tissue culture support surface 66. The first tissue culture support surface 64 is a recessed area that supports separate tissue culture plates 68, 70, and the second tissue culture support surface 66 supports a separate tissue culture plate 72. Interiorly extending tissue guides 74, 76, 78, 80 facilitate tissue construct transfer within the interior area 46 of the bioreactor 12.
The interiorly extending tissue guides 74-80 are rigid pins that at least partially extend (or in this embodiment, wholly extend) into the interior area 46 and between the first tissue culture side 42 and the second tissue culture side 44. The interiorly extending tissue guides 74-80 may be alternately configured than what is illustrated herein. For example, they could be less rigid structures such as sutures, more pronounced rigid structures, or any other form of leg, translation mechanism, guide structure, etc. capable of facilitating translation of a tissue construct thereon. There may be more or less plates and/or guides than what is illustrated herein, as the illustrated embodiment is only an example. The tissue guides 74-80 extend through each of the plates 68-72 such that an exposed portion 82 is situated on the side of each plate that is oriented away from the interior area 46 and more toward the external surfaces 56, 58 of the bioreactor 12 (the exposed portions 82 are visible in
The tissue guides 74-80 are angled such that the distance between them is greater at the plates 68, 70 than at the plate 72. This allows for a first construct to slide up and shorten in length until it reaches the plate 72 during translation due to tension developed by the cells in the construct. In one embodiment, after the first tissue construct reaches its position near the plate 72, the bioreactor 12 is flipped to seed cells on the plate 72 that will delaminate and capture the first tissue construct, thereby forming a complex three-dimensional tissue construct or a multi-phasic tissue construct. The distance between the tissue guides may be fixed depending on the specifications of the graft. In the embodiment illustrated in
As described above, a complex three-dimensional tissue construct includes two or more tissue constructs cultured from two or more cell sources. The cell sources may include the same cell type. In another embodiment, the complex three-dimensional tissue construct is a multi-phasic tissue construct which includes two or more tissue constructs cultured from two or more cell sources, with the cell sources having one or more different types of cells, such as the BLB construct described above. Applications of the formed constructs include repair of rotator cuff or anterior cruciate ligament injuries, to cite a few examples. In an advantageous embodiment, mesenchymal stem cells are used for the first and/or second cell source.
The sloped media support surface 88 also improves media transfer and drainage within the bioreactor 12 and helps prevent media pooling in the corners of the bioreactor. Advantageously, the sloped media support surface 88 is located on the initial base culture side 42 of the bioreactor 12, which is in culture longer than the tissue culture side 44 (in this embodiment, the bone is in culture longer than the ligament, but this could be adapted depending on the desired tissue construct to be formed). The sloped media support surface 88 converges toward the tissue culture support surface 64 at the tissue culture support region 60. In this particular embodiment, the sloped media support surface 88 has four angled walls 98, 100, 102, 104 extending from a lid recess 106 to the port sidewall 84 at the tissue culture support surface 64. The angled walls 98-104 are more clearly shown in
The bioreactor 12 includes a port assembly 54 having a number of ports that help facilitate media transfer within the internal area 46 of the bioreactor. Ports are schematically illustrated by dotted lines in the figures for example purposes, and are not necessarily to scale. Moreover, the size, shape, configuration, etc. of the ports in the port assembly 54 may vary from what is schematically illustrated in the figures. Further, the configuration of the port assembly 54 is different in
Additionally, the feeding ports 112-118 serve as gas outlets to relieve pressure when the bioreactor 12 is in a base side up orientation (e.g., the bioreactor 12 flips). Thus, the feeding ports 112-118 have a secondary purpose, as each interior port opening 86 of the ports 112-118 are flush with the uppermost point in the bioreactor interior area 46 when the bioreactor 12 is flipped (i.e., the second side or lid side 44 is down). This is useful for pressure relief and removing gas while feeding the second tissue culture support region 62, because as liquid media enters the internal area 46, gas goes to the top and needs to exit somehow. Accordingly, with reference to the second tissue culture side 44 or lid side shown in
Returning to
A lid recess 106 may be included in some embodiments to accommodate the extending ridge 132 on the second tissue culture side 44 (lid recess 106 is shown in
As described above, the bioreactor assembly 10 can be selectively controlled in various modes to facilitate media transfer with respect to the bioreactor 12 and/or the port assembly 54.
It is to be understood that the foregoing description is of one or more preferred exemplary embodiments of the invention. The invention is not limited to the particular embodiment(s) disclosed herein, but rather is defined solely by the claims below. Furthermore, the statements contained in the foregoing description relate to particular embodiments and are not to be construed as limitations on the scope of the invention or on the definition of terms used in the claims, except where a term or phrase is expressly defined above. Various other embodiments and various changes and modifications to the disclosed embodiment(s) will become apparent to those skilled in the art. All such other embodiments, changes, and modifications are intended to come within the scope of the appended claims.
As used in this specification and claims, the terms for “example,” “e.g.,” “for instance,” and “such as,” and the verbs “comprising,” “having,” “including,” and their other verb forms, when used in conjunction with a listing of one or more components or other items, are each to be construed as open-ended, meaning that the listing is not to be considered as excluding other, additional components or items. Other terms are to be construed using their broadest reasonable meaning unless they are used in a context that requires a different interpretation. In addition, the term “and/or” is to be construed as an inclusive OR. Therefore, for example, the phrase “A, B, and/or C” is to be interpreted as covering all the following: “A”; “B”; “C”; “A and B”; “A and C”; “B and C”; and “A, B, and C.”
Claims
1. A bioreactor, comprising:
- an external surface;
- a first tissue culture side for culturing a first cell source in a first tissue culture support region;
- a second tissue culture side for culturing a second cell source in a second tissue culture support region; and
- a plurality of ports, wherein at least one of the ports of the plurality of ports extends from the first tissue culture support region of the first tissue culture side to the external surface.
2. The bioreactor of claim 1, wherein the plurality of ports includes an external port that is configured to be a liquid inlet when the bioreactor is in a first orientation and a gas outlet when the bioreactor is in a second orientation.
3. The bioreactor of claim 2, wherein the external port opens from the external surface into a perimeter channel.
4. The bioreactor of claim 1, wherein the first tissue culture side and the second tissue culture side are made from a transparent plastic material.
5. The bioreactor of claim 1, wherein the first tissue culture support region includes a first tissue culture support surface and the second tissue culture support region includes a second tissue culture support surface.
6. The bioreactor of claim 5, wherein the first tissue culture support surface supports two or more separate tissue culture plates and the second tissue culture support surface supports a single tissue culture plate.
7. The bioreactor of claim 6, wherein two media collection reservoirs are situated below the two or more separate tissue culture plates.
8. The bioreactor of claim 7, wherein the two media collection reservoirs include corner projections to help stabilize or position the two or more separate tissue culture plates.
9. The bioreactor of claim 7, wherein the two or more separate tissue culture plates are joined to the single tissue culture plate with a plurality of interiorly extending tissue guides.
10. The bioreactor of claim 9, wherein the interiorly extending tissue guides are angled such that a distance between the interiorly extending tissue guides is greater at the two or more separate tissue culture plates than a distance between the interiorly extending tissue guides at the single tissue culture plate.
11. The bioreactor of claim 5, wherein the first tissue culture support surface is a doubly recessed area that includes a port side wall having port openings from the plurality of ports.
12. The bioreactor of claim 11, wherein the port side wall recesses the first tissue culture support surface away from a sloped media support surface.
13. The bioreactor of claim 12, wherein the sloped media support surface has four angled walls that converge toward the first tissue culture support surface.
14. The bioreactor of claim 13, wherein an angle of each angled wall of the four angled walls is between 3° and 10°, inclusive.
15. The bioreactor of claim 12, wherein the plurality of ports includes feeding ports and seeding ports, and the seeding ports are located closer to the sloped media support surface than the feeding ports.
16. The bioreactor of claim 1, wherein the plurality of ports includes an internal port that extends partly into the first tissue culture side or the second tissue culture side to house a non-invasive sensor.
17. The bioreactor of claim 1, wherein the first tissue culture side includes a lid recess to accommodate an extending ridge on the second tissue culture side.
18. A bioreactor, comprising:
- an external surface;
- a tissue culture side;
- and an external port extending between the tissue culture side and the external surface, wherein the external port is configured to be a liquid inlet when the bioreactor is in a first orientation and a gas outlet when the bioreactor is in a second orientation.
19. A bioreactor, comprising:
- a tissue culture support region having a media collection reservoir, wherein the media collection reservoir is configured to accommodate at least a portion of an interiorly extending tissue guide.
20. A bioreactor, comprising:
- a first tissue culture side for culturing a first cell source;
- a second tissue culture side for culturing a second cell source; and
- a sloped media support surface, wherein the sloped media support surface converges toward a tissue culture support surface in the first tissue culture side or the second tissue culture side.
Type: Application
Filed: May 24, 2020
Publication Date: Aug 4, 2022
Inventors: LISA M. LARKIN (Ann Arbor, MI), ELLEN M. ARRUDA (Ann Arbor, MI), MICHAEL J. SMIETANA (Memphis, TN), PABLO MONCADO-LARROTIZ (San Francisco, CA), HALEY TITINGER (Ann Arbor, MI)
Application Number: 17/614,257